Safety device for motion-picture projectors



H. 0. DREYFUS.

SAFETY DEVICE FOR MOTION PICTURE PROJECTORS.

APPLICATION FILEDAUG.9. 1919.

1,342,429. Patented June 8, 1920.

amwwlioz hf J, $77.5 YFUS mime UNlTED STATES PATENT OFFICE.

HERBERT n. nnn rns, or 'rnnnn HAU'IE, rnnisna.

I SAFETY DEVICE FOR MOTION-PICTURE PROJECTORS.

Specification of Letters Patent.

Patented June 8,1920.

Application filed August 9, 1919. $eria1 No. 316,304.

To all whom it may concern:

Be it known that I, HERBERT D. Dnnvros, a citizen of the United States,residing at Terre Haute, in the county of Vigo and State of Indiana,have invented a new and useful Safety Device for Moving-PictureProjectors, of which the following is a specification. 7

The object of my invention is to produce a device by which breakage ornon-feed of the film in a motion picture projector will automaticallyscreen the film from the projecting light and discontinue the drivingaction upon the film. I

The accompanying drawings illustrate my invention. Figure 1 is a sideelevation, rather diagrammatic in character, of an embodiment of myinvention in conjunction with adjacent parts of the projector; Fig. 2 aplan, in partial horizontal section, oi the parts shown in Fig". 1; andFig. 3 an end elevation of the plunger-releasing mechanism.

in the drawings, 10 indicates the usual light-tube of lamp 11; 12 thefilm-driving gear advanced step by step by motor train 13, driven, in.the present instance, by electric motor 14, in the usual manner; 15 thetake-oil film-driving gear driven by train 13; 16 the loop-setter armcarried by shaft 1? having cam 18 which controls clutch arm 19 actingupon clutch member 20 which cooperates with clutch'mernher 21 carried bypulley 22 connected by belt 23 with the takeup drum (not shown). Asci-called loop of film is thus normally maintained between the gears 12and 15, around finger 16. in Fig. l, the loop referred to is directlysuspended from wheel 15 and an idler 75, hut it will be readilyunderstood that the preeise manner in which the loop is obtainedsustained is not material.' All of the shove parts are well known, asshown, in one well-known type 0'? machine, d counter-carts, either partor, ahle to, other types of machines.

" t at 253 on tube 10, is t to position in contact with terminal 33 andthese two terminals are arranged in the circuit of motor 14.

Lever 31 is connected by link 3 attached to arm 35 of the armature 36 ofelectromagnet 37, said armature, in the form shown, being a rotaryarmature.

Referring now to Figs. 1 and 2, 40 is a frame, or plate, suitably formedas a support for a pivoted gravity arm 41, carrying a roller 42 adaptedto rest lightly on film 4C3, conveniently just beyond take-up wheel 15,so as to hold spring connector 44 out of contact with terminal 4C5.Terminals 45 and 45 are connected with the coil of magnet 37 and anenergizing circuit in any well.- lrnown manner, to control the action ofthe magnet. The action of the magnet is also controlled by terminals 456and it one of which is conveniently attached to arm 19 and the other toframe 40, the arrangement heing such that magnet 37 will he energizedwhenever loop-setter 16 is moved to an abnormal position, due toimproper loop con-- ditions, sufiicient not only to separate clutchmember 20 from clutch member 21, but inn ther to bring terminal 46 intocontact with terminal 4:7.

The operation is as follows: The film is threaded through the machine inthe usual manner, as shown in Fig. 1, and with roller resting lightlythereon so as to hold connector it out of contact with terminals l5 andposition to hold arm 15% so terminal 46 is o it of contact with terminall7 and clutch mom er 20 in engagement with clutch mem- 21. Elhutter 26is to open p tion and thereby pushes plunger to posifon to hold terminalin contact 'errninal 33. "eupon motor 14- he tart ed by itch 50. long;Lu n movement s normal the part d, ere

over n case the 5 up wheel 26 1'50 dra 1 ezms associate ably suppo Wedc06 in cim

